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| United States Patent |
6,248,205
|
|
Scheidmantel
, et al.
|
June 19, 2001
|
Method of fabricating an armrest
Abstract
An armrest adapted to be mounted to a vehicle door comprises a primary
substrate adapted to be mounted to a vehicle door panel with a secondary
substrate mounted to the primary substrate and defining a recess. A foam
layer is mounted to the secondary substrate within the recess, and a
flexible outer casing intergrally molded to the primary substrate forming
a recess with the primary substrate which receives the secondary substrate
and the foam layer. A method of fabricating the armrest for the vehicle
door is also provided.
| Inventors:
|
Scheidmantel; David A. (Rockford, MI);
Versaw, Jr.; Robert H. (Muskegon, MI)
|
| Assignee:
|
Leon Plastics, Inc. (Grand Rapids, MI)
|
| Appl. No.:
|
525163 |
| Filed:
|
March 14, 2000 |
| Current U.S. Class: |
156/309.6; 248/118; 296/153; 297/227; 297/411.21 |
| Intern'l Class: |
B60J 009/00 |
| Field of Search: |
156/309.6
296/153
297/227,228,411.2,411.21
248/118
|
References Cited
U.S. Patent Documents
| 2601677 | Jun., 1952 | Wettlaufer.
| |
| 2661052 | Dec., 1953 | Bushong.
| |
| 2703602 | Mar., 1955 | Greenstadt.
| |
| 2914119 | Nov., 1959 | Keefe, Jr.
| |
| 3279853 | Oct., 1966 | Cromwell et al.
| |
| 3387881 | Jun., 1968 | Stepanek et al.
| |
| 3620566 | Nov., 1971 | Leconte.
| |
| 4869543 | Sep., 1989 | Grimes.
| |
| 5290087 | Mar., 1994 | Spykerman.
| |
Primary Examiner: Ball; Michael W.
Assistant Examiner: Rossi; Jessica
Attorney, Agent or Firm: Rader, Fishman, Grauer & McGarry, an Office of Rader, Fishman & Grauer PLLC
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No.
09/389,971, filed Sep. 3, 1999, which application claims the benefit of
U.S. patent application Ser. No. 60/099,649, filed Sep. 9, 1998.
Claims
What is claimed is:
1. A method of fabricating a vehicle door armrest comprising the steps of:
forming a primary substrate adapted to be mounted to a vehicle door panel;
integrally molding a flexible outer casing to the primary substrate and
forming a recess therewith;
forming a secondary substrate having a mounting platform with a shape
adapted to occupy a lower portion of the recess defined by the primary
substrate and the outer casing;
forming a foam pad having a shape adapted to occupy the remainder of the
recess between the mounting platform and the outer casing;
mounting the foam pad to the mounting platform of the secondary substrate;
inserting an assembly of the foam pad and the secondary substrate into the
recess defined by the primary substrate and the outer casing.
2. The method of claim 1 wherein the step of mounting the foam pad to the
secondary substrate comprises adhesively securing the foam pad to the
secondary substrate.
3. The method of claim 1 wherein the foam pad has a substantially uniform
thickness.
4. The method of claim 1 wherein the step of forming the foam pad comprises
die cutting the foam pad.
5. The method of claim 1 wherein the primary substrate and the secondary
substrate are formed of a thermoplastic material and further comprising
the step of heat fusing the secondary substrate to the primary substrate.
6. The method of claim 5 wherein the step of heat fusing comprises heat
staking.
7. The method of claim 6 wherein the step of mounting the foam pad to the
secondary substrate comprises adhesively securing the foam pad to the
secondary substrate.
8. The method of claim 7 wherein the flexible outer casing is a
thermoplastic material.
9. The method of claim 8 wherein the molded thermoplastic material
comprises a vinyl resin.
10. The method of claim 9 and further comprising the step of inserting a
portion of the primary substrate into a portion of the secondary substrate
to align the primary and secondary substrates with respect to one another.
11. The method of claim 10 and further comprising the step of heat fusing
the primary substrate to the secondary substrate.
12. The method of claim 11 wherein the step of heat fusing comprises the
step of heat staking the primary substrate to the secondary substrate
through an opening in the secondary substrate.
13. The method of claim 12 wherein the step of inserting a portion of the
primary substrate into a portion of the secondary substrate comprises the
step of inserting at least one depending locator pin on the secondary
substrate into at least one opening in the primary substrate.
14. The method of claim 1 wherein the mounting platform has a wedge shape
from a rear portion to a front portion thereof for facilitating the step
of inserting the assembly of the foam pad and the secondary substrate into
the recess defined by the primary substrate and the outer casing.
15. The method of claim 14 wherein the foam pad has a substantially uniform
thickness.
16. The method of claim 15 wherein the step of forming the foam pad
comprises die cutting the foam pad.
17. The method of claim 1 wherein the flexible outer casing is a
thermoplastic material.
18. The method of claim 17 wherein the molded thermoplastic material
comprises a vinyl resin.
19. The method of claim 1 and further comprising the step of inserting a
portion of the primary substrate into a portion of the secondary substrate
to align the primary and secondary substrates with respect to one another.
20. The method of claim 19 wherein the step of inserting a portion of the
primary substrate into a portion of the secondary substrate comprises the
step of inserting at least one depending locator pin on the secondary
substrate into at least one opening in the primary substrate.
21. The method of claim 1 and further comprising the step of heat fusing
the primary substrate to the secondary substrate.
22. The method of claim 21 wherein the step of heat fusing comprises the
step of heat staking the primary substrate to the secondary substrate
through an opening in the secondary substrate.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a vehicular armrest, and more particularly, to an
armrest having a structural substrate, a vinyl or flexible polyolefin
covering and a foam filling between the substrate, secondary substrate and
cover and the vinyl covering. The invention also relates to a process for
fabricating the vehicular armrest.
2. Related Art
Armrests filled with polyurethane foam resins have been mounted on vehicle
doors for many years. An example of a prior art armrest 110 is shown in
FIG. 1 comprising a structural plastic or metal internal support 112
having a substrate surface 120, a vinyl or flexible polyolefin outer cover
118 and a polyurethane or similar foam filling 146 enclosed within the
internal support 112 and cover 118 by a panel 114.
While such conventional foam materials have been readily utilized in the
industry, problems have been identified with respect to, among other
things, the consistency of their reaction profiles. For example, armrests
110 are conventionally filled with a two-part polyurethane foam.
Polyurethanes are generically prepared by nucleophilic addition of
alcohols to isocyanates. Foaming occurs when a small amount of water is
added to the two chemical reagents during polymerization. Specifically,
water adds to the isocyanate groups providing carbamic acids, which
spontaneously lose carbon dioxide, thus generating bubbles and, in turn,
foam within the curing polymer.
When the polyurethane foam 146 is poured into the armrest 110 during the
initial stages of polymerization the reagents are still susceptible to
parameter changes such as atmospheric moisture (humidity), temperature,
and pressure changes. These parameter changes can have a substantially
adverse impact upon the consistency of the resulting foam 146 from day to
day or even batch to batch. Furthermore, according to conventional
methods, after the two-part polyurethane foam 146 has been poured and
cured, copious quantities of scrap remain, which requires additional time
and labor to clean up and, in turn, adds to the cost of production.
Moreover, the disposal of the scraps and byproducts from synthesizing
polyurethanes can be costly.
In addition, due to the complexity, smell, and messiness of preparing
polyurethane foams, it is typically not practical for the armrest 110 to
be assembled in one location as the preparation of the foam 146 requires
an additional, separate work station which further adds to the cost of
manufacturing. Further, the polyurethane foams 146 are not recyclable and
thus the armrests 110 are not recyclable when the automobile is eventually
scrapped.
SUMMARY OF THE INVENTION
In one aspect, the invention relates to an armrest adapted to be mounted to
a vehicle door comprising a primary substrate adapted to be mounted to a
vehicle door panel and a secondary substrate mounted to the primary
substrate and defining a recess. A foam layer is mounted to the secondary
substrate within the recess, and a flexible outer casing is integrally
molded to the primary substrate forming a recess with the primary
substrate which receives the secondary substrate and the foam layer.
The primary substrate and the secondary substrate can be formed of a
thermoplastic material and the secondary substrate is heat fused to the
primary substrate. The heat fusing can comprise heat staking. The foam
layer can be adhesively secured to the secondary substrate. The foam layer
can be unsecured to the flexible outer casing. The flexible outer casing
can be a molded thermoplastic material. The molded thermoplastic material
can comprise a vinyl resin. The secondary substrate can have a depending
flange with an opening and the primary substrate can have an alignment tab
positioned in the opening. The secondary substrate can have a second
opening and the primary substrate can be heat staked to the secondary
substrate through the second opening. The secondary substrate can have at
least one depending locator pin and the primary substrate can have at
least one opening which receives the at least one depending locator pin.
The secondary substrate can have a wedge-shaped platform which has an
upper surface which receives the foam layer. The foam layer can have a
substantially uniform thickness. The foam layer can be formed of a vinyl
resin which is die cut. The secondary substrate can have a generally
vertical wall with at least one flange extending rearwardly therefrom,
wherein the at least one flange is adapted to locate the armrest in an
opening on a vehicle door. The components of the armrest can be formed
from recyclable materials. The primary substrate can have a flexible
depending detent arm adapted to locate the armrest within an opening on a
vehicle door. The outer casing can have a tab on an interior surface
thereof which extends between a portion of the primary substrate and the
secondary substrate whereby the tab wedges between the substrates and
reduces vibratory noise therebetween.
In another aspect, the invention relates to a method of fabricating an
armrest for a vehicle door comprising the steps of forming a primary
substrate adapted to be mounted to a vehicle door panel; intergrally
molding a flexible outer casing to the primary substrate and forming a
recess therewith; forming a secondary substrate having a mounting platform
with a shape adapted to occupy a lower portion of the recess; forming a
foam layer having a shape adapted to occupy the remainder of the recess
between the mounting platform and the outer casing; mounting the foam
layer to the mounting platform of the secondary substrate; and inserting
the assembly of the foam layer and the secondary substrate into the recess
defined by the primary substrate and the outer casing.
The elements produced by the above method can have the features described
above with respect to the armrest. Further, the method can include the
steps of heat fusing and/or heat staking the secondary substrate to the
primary substrate; mounting the foam layer to the secondary substrate and
adhesively securing the foam layer to the secondary substrate; inserting a
portion of the primary substrate into a portion of the secondary substrate
to align the primary and secondary substrates with respect to one another;
heat fusing the primary substrate to the secondary substrate; heat staking
the primary substrate to the secondary substrate through an opening in the
secondary substrate; inserting at least one depending locator pin on the
secondary substrate into at least one opening in the primary substrate;
and die cutting the foam layer.
The mounting platform can have a wedge shape from a rear portion to a front
portion thereof for facilitating the step of inserting the assembly of the
foam layer and the secondary substrate into the recess defined by the
primary substrate and the outer casing. The foam layer can have a
substantially uniform thickness.
Other objects, features, and advantages of the invention will be apparent
from the ensuing description in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
The invention will now be described with reference to the drawings wherein:
FIG. 1 is a cross-sectional view of a prior art armrest filled with a
two-part polyurethane foam;
FIG. 2 is an exploded perspective view of a first embodiment of an armrest
in accordance with the present invention utilizing a die-cut vinyl nitrile
or polyolefin-based foam;
FIG. 3 is a cross-sectional view of the armrest of FIG. 2 taken along lines
3--3;
FIG. 3A is a cross-sectional view of a first embodiment of a mounting post
employed with the armrest of FIG. 1 taken along lines 3A--3A of FIG. 3;
FIG. 3B is a cross-sectional view of a second embodiment of the mounting
post employed with the armrest of FIGS. 2-3;
FIG. 3C is a cross-sectional view like FIG. 3A taken along lines 3C--3C of
FIG. 3B;
FIG. 4 is an exploded perspective view of a vehicle door being assembled
with an armrest in accordance with the present invention.
DETAILED DESCRIPTION
Referring now to the drawings and to FIG. 2 in particular, a first
embodiment of an armrest 10 is shown which generally comprises a primary
substrate 12, a secondary substrate 14, a die-cut foam filler 16, and an
outer casing 18.
As best shown in FIGS. 2-3, the primary substrate 12 provides for the
general structure and contour of the armrest 10, and can be configured in
any one of a number of shapes. The primary substrate 12 includes a
substantially planar ridge 20 for receiving the secondary substrate 14.
The primary substrate 12 further includes an alignment tab 22 which
emanates outwardly from the planar ridge 20 and which is received, upon
assembly, by a slot 24 of the secondary substrate 14 to facilitate proper
transverse alignment between the primary and secondary substrates 12 and
14.
The primary substrate 12 further includes an L-shaped member 26 emanating
substantially outwardly and downwardly proximate the lower surface of the
planar ridge 20. The L-shaped member 26 is used in two capacities. First,
the L-shaped member 26 is used to align the armrest 10 with an aperture of
a vehicle door 44 (shown in FIG. 4). Second, the L-shaped member 26 adds
stability to the armrest 10, once the armrest 10 is secured to the door
44.
Moreover, the primary substrate 12 includes a plurality of fastener
receivers 28 for receiving fasteners, such as, but by no means limited to,
threaded screws to, in turn, secure the armrest 10 to the door of a
vehicle. The fastener receivers 28 are shown by example in FIG. 2 as
comprising a molded cylindrical boss having a longitudinal threaded bore
therein.
The primary substrate 12 is preferably fabricated from glass filled
polypropylene. However, any one of a number of materials can be used to
fabricate the primary substrate 12 including, but by no means limited to
wood, steel and various metallic alloys, and numerous other synthetic
resin compounds. Of course, the precise fabrication materials used will
depend upon the particular qualities desired such as price, weight,
strength, durability, or any combination thereof.
The secondary substrate 14, as shown in FIGS. 2-3, comprises a generally
vertical cover 30 having a slot 24 adapted to receive the tab 22 of the
primary substrate 12 upon assembly. In addition, the vertical cover 30 has
a second slot 34 adapted to receive a heat-staking tool upon final
assembly of the armrest 10 to mount the secondary substrate 14 to the
primary substrate 12. As best shown in FIG. 3, the vertical cover 30
preferably has a locking groove 50 adjacent an upper edge thereof which
creates a channel to secure outer casing 18 thereto--which has a casing
bead 52 adapted to snap-fit within the locking groove 50. This locking
feature prevents the outer casing 18 from distorting when mounted in
abutment to the door panel 44.
A mounting platform 32 emanates substantially perpendicular from the
generally vertical cover 30. The mounting platform 32 is generally planar
and geometrically conforms to the planar ridge 20 of the primary substrate
12. As shown in FIG. 3, the mounting platform 32 preferably has a tapering
wedge-shaped cross-section.
The mounting panel 32 of the vertical cover 30 also preferably includes a
number of locators 48 which facilitate proper alignment between the
primary substrate 12 and the secondary substrate 14. The locators 48
accurately position the secondary substrate 14 with respect to the primary
substrate 12 for different vehicles and to lock the secondary substrate
thereto after assembly. The locators 48 can be integrally molded with the
L-shaped member 26 as desired when design constraints permit.
FIGS. 3-3A show a first embodiment of the locator 48 in detail comprising a
cylindrical member 48a having a ramped distal surface 48b thereon. FIGS.
3B-3C show a second embodiment of a locator 48' in detail comprising an
elongated member 48c having an elliptical or rounded rectangular cross
section and also having a ramped surface 48d thereon.
The secondary substrate 14 is preferably fabricated from acrylonitrile
butadiene styrene (ABS) polymers or a polyolefin-based resin. However, any
one of a number of materials can be used to fabricate the secondary
substrate 14 including, but by no means limited to wood, steel and various
metal alloys, and numerous other synthetic resin compounds.
The foam filler 16 provides a "spongy" feel to an occupant who places
his/her arm upon the armrest 10. The foam filler 16 includes an upper
surface 36 and a lower surface 38. Applied to the lower surface 38 of the
foam filler 16 is a conventional pressure sensitive adhesive. Prior to
final assembly, the adhesive is protected with a paperboard covering 40.
The surface of the paperboard covering 40 that contacts the pressure
sensitive adhesive is coated with a conventional material to preclude
adhesion between the foam filler 16 and the paperboard covering 40. While
the pressure sensitive adhesive has been disclosed as applied to the foam
filler 16, for illustrative purposes only, it is likewise contemplated
that the adhesive can be applied to the mounting platform 32 of the
secondary substrate 14.
The foam filler 16 is preferably die-cut to conform to the geometric
configuration of both the mounting platform 32 of the secondary substrate
14 as well as the planar ridge 20 of the primary substrate 12. The foam
filler 16 is preferably fabricated from vinyl nitrile resins. However, any
one of a number of polymeric resins, such as EPDM, polypropylene,
polyethylene, etc., are likewise suitable for use. The vinyl nitrile
resins are preferred for at least two reasons. First, the vinyl nitrile
cured resins are ideal for conventional die-cutting. As such, all
components of the armrest can be collected and assembled in one final
assembly location which, in turn, reduces the cost of production. Second,
the vinyl nitrile cured resins result in a foam that is especially spongy
which gives the armrest a softer feel when a occupant rests his/her arm
upon the region having such a foam filler.
The outer casing 18 is molded to generally conform the geometric
configuration of the primary and secondary substrates 12 and 14
collectively--when assembled. The outer casing 18 is preferably fabricated
from polyvinyl chloride (PVC). However, any one of a number of
conventional casing materials are likewise contemplated for use including
known thermoplastic polyolefin-based elastomers, for example.
As best shown in FIG. 3, the outer casing 18 is also provided with an outer
tab 54 which extends inwardly therefrom to nest between the primary
substrate 12 and an outer edge of the secondary substrate 14. The outer
tab 54 effectively functions as a wedge between the primary and secondary
substrates 12 and 14 and the outer casing 18 to prevent noise from being
generated within the armrest 10 during use as a result of vibration of the
vehicle.
As will be readily apparent from the description below, the armrest 10 in
accordance to the present invention is suitable for final assembly in one
location using only a limited number of nominal manual steps.
To initiate assembly of the armrest 10, the primary substrate 12 is placed
in a mold conforming to the geometric configuration of the outer casing
18. The outer casing 18 is then applied over the primary substrate 12 by
injecting outer cover material into the mold. Such a process is
conventionally known as "insert molding" or "over molding." As best shown
in FIG. 2, once the outer cover material is cured, the partially
fabricated armrest includes a channel 42 for receiving both the secondary
substrate 14 and the foam filler 16.
Upon further assembly, the paperboard covering 40 of the foam filler 16 is
removed thus exposing the pressure sensitive adhesive which is applied to
the lower surface 38 of the foam filler 16. Once the paperboard material
40 is removed, the lower surface 38 having the pressure sensitive
adhesive, is fixedly applied to the upper surface of the platform 32 of
the secondary substrate 14. Next the secondary substrate 14, with the
applied foam filler 16, is inserted into the channel 42. To assure proper
alignment, the slot 24 of the secondary substrate 14 receives the tab 22
of the primary substrate 12 upon such an insertion.
In addition, the locators 48 on the secondary substrate 14 can be
positioned within corresponding apertures or openings in the primary
substrate for further location assistance between the two substrates 12
and 14. The ramped surface 48b on the locators assist insertion of the
locators 48 within the openings in the primary substrate 12 by allowing
the secondary substrate 14 to slide relative to the primary substrate 12
in an angular fashion and then allowing pivoting to an abutted
relationship when the proper alignment is obtained.
After the secondary substrate 14 is fully inserted into the channel 42,
assembly of the armrest 10 is completed by fusing together the primary and
secondary substrates 12 and 14, respectively. Fusion of the two substrates
is preferably accomplished by inserting a conventional heat staking tool
into and through the slot 34 of the secondary substrate 14 thereby
contacting a portion of both the primary and secondary substrates 12 and
14, respectively, and, in turn, fusing the two substrates 12 and 14
together. While conventional heat staking has been described herein, for
illustrative purposes only, any one of a number of "fusing" and/or
"sealing" procedures known to those having ordinary skill in the art are
likewise contemplated for use. Attachment could also be accomplished via
screws, rivets, adhesives etc.
As shown in FIG. 3, upon complete assembly of the armrest 10, the die-cut
foam filler 16 is wedged between the secondary substrate 14 and the outer
casing 18. The die-cut foam filler 16 does not contact the planar ridge 20
of the primary substrate 12. In comparison with the prior art armrest
assembly shown in FIG. 1, a fully assembled prior art armrest utilizing a
poured polyurethane filler 46 does, indeed, contact the planar ridge 20 of
the primary substrate 12.
As shown in FIGS. 3-4, after the armrest 10 of the present invention is
fully assembled, it is then ready for attachment to a door 44 of a
conventional vehicle. To attach the armrest 10 to the vehicle door 44, a
plurality of fasteners are fixedly received into the fastener receivers 28
of the primary substrate 12. Further, to increase the location and
appearance of the armrest 10 when it is mounted to the vehicle door 44,
the primary substrate 12 can be provided with a reversely-extending blade
56 which has a depending detent arm 58 thereon. The detent arm 58 is
adapted to engage within an opening on the vehicle door 44 and is
preferably biased to draw the armrest 10 and vehicle door 44 together. In
this manner, the detent arm 58 on the blade 56 is used to control the
appearance gap of the armrest 10 relative to an exterior panel of the
vehicle door 44 by acting as vertical locator of the armrest 10 to the
door 44. The detent arm 58 also assists the assembly of the armrest
10--for example, the detent arms 58 on the blade 56 can be temporarily
mounted to an arm on a manufacturing assembly to allow the armrest 10 to
be easily handled prior to fusing the substrates 12 and 14 together at the
assembly plant.
It should also be noted that where a flexible polyolefin-based outer cover
is used in conjunction with a polyolefin-based foam 16 and primary and
secondary substrates 12 and 14, the resultant armrest 10 assembly is
completely recyclable. This is due to the compatibility of the components
making up the armrest 10. Thus, even if the armrest 10 is scrapped after
its useful lifetime, the components 12-16 of the armrest 10 can be
recycled.
While particular embodiments of the invention have been shown, it will be
understood, of course, that the invention is not limited thereto since
modifications may be made by those skilled in the art, particularly in
light of the foregoing teachings. Reasonable variation and modifications
are possible within the scope of the foregoing disclosure of the invention
without departing from the spirit of the invention.
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